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arXiv · 1803.10573

Influence of anisotropic $Λ/Σ$ creation on the $Ξ^-$ mutiplicity in subthreshold proton-nucleus collisions

Miklós Zétényi·György Wolf
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Abstract

We present an analysis of $Ξ^-$ baryon production in subthreshold proton--nucleus ($p+A$) collisions in the framework of a BUU type transport model. We propose a new mechanism for $Ξ$ production in the collision of a secondary $Λ$ or $Σ$ hyperon and a nucleon from the target nucleus. We find that the $Ξ^-$ multiplicity in $p+A$ collisions is sensitive to the angular distribution of hyperon production in the primary $N+N$ collision. Using reasonable assumptions on the unknown elementary cross sections we are able to reproduce the $Ξ^-$ multiplicity and the $Ξ^-/(Λ+Σ^0)$ ratio obtained in the HADES experiment in $p$+Nb collisions at $\sqrt{s_{NN}} = $ 3.2 GeV energy.

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Miklós Zétényi, György Wolf. 2018-09-10. Influence of anisotropic $Λ/Σ$ creation on the $Ξ^-$ mutiplicity in subthreshold proton-nucleus collisions. https://doi.org/10.1016/j.physletb.2018.08.054

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